There are numerous requirements for the storage and retention of data, program and other types of information.
In the prior art punched paper tape, magnetic tape and magnetic disks have been used to store and retain such data. More recently the advantages of electrooptic techniques have brought about the use of read-only memories employing photographic film to record the data. When used together with photodiode arrays the light energy transmitted through such a record on photographic film may be readily detected and converted to electrical signals. Such techniques, however, even though offering the advantages of electrooptic processing of data and other types of information, nonetheless suffer from the disadvantages of a great multiplicity of elements such as the photodiodes required, for instance. There are further problems resulting from the requirement for a great multiplicity of photodiodes such as excessive size relative to microfilming techniques available for recording on photographic film. Moreover, a high degree of complexity inhers in the many individual electrical connections required for the great multiplicity of such photodiodes required to provide the desired degree of optical resolution.
Accordingly, there is a need for an electrooptic read-only memory system which is extremely small in size, reliable in operation, adaptable to read-out different recorded information as desired, and embodying the advantages of the most advanced technological features as incorporated in solid state devices.